Electrical condenser



March 18, 1924; I 1,487,096

L. F. FULLER ELECTRICAL CONDENSER Filed June 16'. 1919 WITNESS VENT FULL I ATTbRNEYs Patented Mar; 18, 1924.

UNITED, STATES PA NT orrrcr..-

LYDHA BDI. FULLER, OI PALO AI/IO, CALI'I OBNIA ASSIGNOB, BY Km]; ASSIGN- ma's, '1'0 FEDERAL TELEGRAPH COIPAHY, 01 SAN FRANCISCO, ,cn.rroama, 'A

CORPORATIOI OI CLLIIOBSIA.

WHICH OONDEIIBB.

To all whom z'twnay concern:

Be it known that I, Lsoruan F. Forum, a citizen of the United States, and a resident of Palo Alto, county of Santa Clara, 5 and State of California, have invented a certain new and usefulElectrical Condens- Another object of the invention to'ina 1 5 caease the corona voltage of a condenser.

The invention possesses other advantaeous features, some of which, with the ore-going,- will be set forth at length in the following description where I shall outline in full, that form of the invention which. I

have selected for illustration in thedraw- 'ngs accompanying and forming part of the present specification. v

The construction of this invention is par- I ticularly applicable to condensers consisting of alternate layers of micaor .cther dielectric and metal foil. When condensers of this nature are employed in continuous oscillation radio transmission systems, so corona forms at the ends of the condenser and it is the object of my invention toprevent or greatly reduce the production of corona. I have found that it is possible to greatly increase the voltage a condenser will withstand by arranging flux distributors at the ends of the condenser. The function of the flux distribution shields is to eliminate all sh edges and points at the ends of the con enser. and-thereby incrcasethe voltage at which the corona will form. I In the accompanyin drawings; Figure 1 is a vertica longitu 1 section through a condenser constructed 4a ance with my invention. a Fig. 2 is a vertical'section through one -ol the flux distributing shields.

Fig. 3 is a front elevation of one tifthe shields.

.50 The device of my invention comprises a condenser 2, formed of alternate layers of mica or other dielectric and metal foil, with The shields are sheets of metal foil at the ends a the series of layers. Arranged at the ends of the condenser and in contact with the end metallic layers are metallic flux distributing-shields 4, preferably formed of brass or aluminum. The flux distributing shields are formed with curved surfaces of comparatively large radius, presenting no sharp edges which would encourage the production of corona. referably formed with a large peripheral ad .5, of circular or substantially circular cross-section and within the bead, the body of the shield is de ressed, forming a recess 6, in which the end of the condenser is disposed. The bead joins the body in smoothcurves, thereb eliminating all sharp edges from the shie d. The condenser plate's themselves may he formed with rounded corners, instead of sharp corners, to further discourage the formation of corona.

The condenser, with the shields arranged onlthe ends, is.embedded in a suitable insulating compound 7, such as a mixture of and t e terminals and the insulators are formedwith smooth curved surfaces, to discourage the formation of corona.

My invention involves not only a means for discouraging the formation of corona,

beeswax, parafline androsin, which is conwhich permits the condenser to-withstand a much higher voltage, but also includes a method of increasing the working voltage of a condenser by increas ng its corona volt-age.

Ic arm:

1. In an electrical vcondenser having a pair of terminal plates, a metallic shield aving a surface enga 'ng substantially the entire free surface 0 one of the terminal plates, said. shield having smooth and rounded surfacesonly. A

2. In an electrics condenser having a gait of terminal plates, a metallic shield a onryed 'pheralbead surrounding a re- 10' aving a bead forminiszarecess, said cesa 1n-w ich the end of the condenser is' e and recesse su ntially the entire disposed. I free surface of one of the terminal';platea, In testrmony whereof, I have hereunto I said shield having smooth and rounded snrset myhand at San Francisco, California,

' a this 7th day of June, 1919.

faces onl e 3. The?combination-with a condenser of. LEONARD'RFULLER." metallic plates" arranged at the ends of the In presence. of- 1 condenser, 656i! plate being provided with n. G. Pacer. 

